<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>弱引用案例 - 回收</title>
</head>

<body>

  <script>
    ; (function () {
      let target = {};
      let wr = new WeakRef(target);

      setTimeout(() => {
        window.gc();
        setTimeout(() => {
          let obj = wr.deref();
          if (!obj) {
            console.log("target 对象已被回收");
          } else {
            console.log("target 对象未被回收");
          }
        }, 3000);
      }, 100);
    })();

  </script>

</body>

</html>